Reconnect drain (drainPendingDeliveries) matches fresh pending entries by
design to preserve crash-replay, but the live delivery path in
deliverOutboundPayloads held no in-memory claim while the send was running.
A reconnect firing mid-send therefore re-drove the same queue entry and
produced duplicate outbound messages (e.g. WhatsApp cron sends going out
7-12x when the 30-minute inbound-silence watchdog fired during delivery).
Claim the queueId against the existing entriesInProgress set right after
enqueueDelivery and release it in the finally branch around ack/fail. Drain
already skips claimed ids via claimRecoveryEntry, so no drain-side change is
needed. The claim is process-local on purpose: a crashed owner leaves no
claim behind, so startup recovery still reclaims orphaned entries.
Fixes#70386.
Made-with: Cursor
Address adversarial review finding on #70295: the prior swallow-on-benign
fix silently dropped short replies to Slack Connect users. The SDK's
ChatStreamer buffers text locally until buffer_size (256 default), so
short replies never trigger chat.startStream via append(). streamer.stop()
then issues startStream internally; on Slack Connect recipients this
throws user_not_found. With the prior fix that error was swallowed and
the dispatcher marked the turn delivered - user saw 'done' reaction but
no message.
SlackStreamSession now tracks delivered (true once any Slack API call
returned a response) and pendingText (accumulation of every append +
final-stop text). stopSlackStream:
- swallows the benign code when delivered=true (prior append flushed;
text is visible; same behavior as before)
- throws a new SlackStreamNotDeliveredError carrying pendingText when
delivered=false (nothing reached Slack)
dispatch.ts catches SlackStreamNotDeliveredError and posts pendingText
via a rename-bound chat.postMessage (to dodge the unicorn lint rule),
and flips streamFallbackDelivered so anyReplyDelivered stays correct.
Fixes#70295
When Slack's chat.stopStream fails with user_not_found (Slack Connect DM
recipients), team_not_found (cross-workspace shared channels), or
missing_recipient_user_id (DM closed mid-stream), the text already
delivered via append() is still visible to the user. Swallow those
specific codes and mark the session stopped rather than surfacing a
spurious 'slack-stream: failed to stop stream' error in dispatch. Other
Slack API errors still propagate.
Fixes#70295
